This invention relates to programmable logic device integrated circuits, and more particularly, to testing programmable logic device integrated circuits.
Programmable logic devices are a type of integrated circuit that can be customized by a user to implement a desired logic design. In a typical scenario, a logic designer uses a logic design system to design a logic circuit. The logic design system uses information on the hardware capabilities of a given programmable logic device to help the designer implement the logic circuit using the resources available on the given programmable logic device. The logic design system creates configuration data. When the configuration data is loaded into the programmable logic device, it programs the logic of the programmable logic device so that the programmable logic device implements the designer's logic circuit.
It is generally desirable to test programmable logic device integrated circuits during manufacturing. If a fault is detected, a programmable logic device integrated circuit can be repaired or discarded.
During testing, a programmable logic device is loaded with sets of test configuration data. After each set of test configuration data has been loaded, test vectors are applied to the device and the resulting operation of the device is monitored to identify faults.
Unless a programmable logic device design contains only simple patterns of conductive interconnects and programmable connections, it can be computationally intensive to generate appropriate sets of test configuration data and test vectors to be applied to the device during testing. Modern programmable logic devices often have complex architectures and are highly programmable. The highly-programmable nature of these devices makes it challenging to efficiently produce test configuration data and test vectors that will provide an acceptable level of test coverage.
It would therefore be desirable to provide improved ways in which to test programmable logic device integrated circuits.